Various techniques for X-ray analysis are known in the art, such as measurement of X-ray diffraction, reflectivity, fluorescence, or other types of scattering from a sample. Typically, each type of measurement requires an X-ray beam with certain qualities, such as collimation (i.e., angular spread of the beam), monochromatization (range of photon energies), and focal size (beam width on the sample). In general, the desired qualities may vary depending on the type of sample and objectives of the measurement. The beams that are output directly by common X-ray sources, however, such as metal-anode X-ray tubes, for the most part do not meet these quality constraints.
To overcome these limitations, X-ray optical elements have been developed to enhance beam collimation, monochromatization and focal properties. For example, a variety of X-ray mirrors are commercially available to collect and then collimate and/or focus an X-ray beam, such as multi-layer mirrors made by AXO DRESDEN GmbH (Dresden, Germany) and Rigaku Corporation (Tokyo, Japan). As another example, to achieve particularly fine collimation and monochromaticity, the X-ray beam may be reflected through a channel in a crystal of highly-perfect silicon or germanium, such as channel-cut crystals manufactured by Crystal Scientific (UK) Ltd. (Alnwick, Northumberland, UK).
Some X-ray measurement systems are designed to accommodate adjustable and/or interchangeable optics, to enable the user to vary or select beam properties to suit different types of measurements. This sort of capability is available in certain commercially-available systems, such as the D1 Evolution system produced by Jordan Valley Semiconductors Ltd. (Migdal Ha′emek, Israel). Multifunction systems of this sort are described in the patent literature, for example, in U.S. Pat. Nos. 7,120,228 and 7,551,719, whose disclosures are incorporated herein by reference. X-ray diffractometers with interchangeable optical features are also described, for example, in U.S. Pat. Nos. 6,665,372, 7,711,091 and 7,684,543.